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Feb/March Lite Challenge: Mangrove River Postcard

Saw this old postcard, and immediately started thinking of where I could use the style, or something close. The fact that the printing was a little rough could play well with my level of sophistication :-).

The map for these contests has to be new, but the geography can already exist. As I thought of what river could be postcarded like this, I drifted to the geofiction world I participate in (well, participated - it's stagnant just now). Always the contrarian, I wanted to see how many of the usual river rules - like those posted in the Feb/Mar announcement - that i could break or bend, and yet maintain plausibility & hydrology. Years ago I devised a tropical nonplayer nation in Aurora, named Wondusoland.

Now, the Florida Everglades is not JUST a swamp, it is also known as the River of Grass. There's sufficient directional flow year-round to call the whole thing a river 80 km wide. Well, that suits my exception-to-the-rules premise...

So starting with one of the maps I already had of the area as a reference:

I then figured whether anything needed to be tweaked. I generally try to keep continuity with other players' geographic data, and with anything I've already documented. I don't have any explicit topographic data on the area, so assuming it a bit flatter than that reference map indicates suits my contest purpose. Seems like somewhere I even had mangroves as a feature of the western edge of the depicted landmass, and alligators, and bayous and swamps, so that fit just fine. What to call the thing? Well, the continent is an Africa-analogue, very roughly, so some of the names will be in the local tongues... no conlangs here, just enough borrowed syllables to convey an impression. But the postcard would be for tourists so the title might as well be in English. Voila:

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That's the first thing that's enough of a new map to tag as WIP. No automation here, I traced all the needed outlines from the reference. I'm working at twice this size and reducing for posting.

The river tracks on there look to be mostly Fractal-Terrain generated; they'll all go away for this map. But they serve as an indicator of the general topography - I'll trace what I need, or invent new alignments. It's a postcard - why should it be assumed to be accurate? Probably printed six thousand km away anyway, and published by people whose only tie to the region is profit.

Which of those squiggles IS the Mangrove river? Well, I figure a postcard would highlight the whole vague squishy oozing directional swamp something like this:

### Latest WIP ###

I know a threaded channel doesn't break any of the usual river rules, it is just an edge case. Well, this is an over-the-edge case :-) , with a gazillion channels and another gazillion hummocks, islets, ash-bars (did I mention the volcanoes upriver?), individual trees, and dubious navigability. Locals use poled flatboats drawing mere inches, and I'm sure there are enough deeper channels, albeit shifting ones, to get modest motor launches through.

What DOES break a usual rule, is the outlet of those lakes. If you look at it as one river, "only one outlet" stands as stated. From the ground (or water... or mud... or back of a gator) though it would in effect be a hundred or more channels leaving from a downstream lakeshore many miles long. Exactly like the Everglades used to leave Lake Okeechobee. "Modern" notions about what is useful land use & water use put a dike along Okeechobee's rim, and has tried to drain the land for agriculture. Only in recent decades have people begun to realize what a horrible idea that was; the massive wetlands need to work free-flow, not "managed". Canals in the area are even being filled in and the meandering channels restored.

Wondusoland has had no such management, other than an occasional dredged channel to get bigger boats from here to there. Aurora is set in an analogue of Earth's 1940's / 1950's, and the country itself is a backwater in every possible meaning of the term.

Another way to break or bend the multiple outlet rule is for a lake to have a dead-level hard rim. That can happen; mineral deposits can build up what's called Travertine Dams - picture the scene at various hot springs around our world. On a big enough scale.... Lake Junumbele. So here I'm assuming the innate geochemistry of the area is prone to those formations, and that the volcanoes at Wondusoland's NE edge produce copious amounts of ash. Build that up, and you could get wide-overflow waterfalls miles wide. The exact width would change as flow breaks through here or there, but unlike a normal eroding lake outlet, travertine dams have a tendency to heal breaches.

This is an inhospitable jungle-y isthmus - land continues off to the ESE and WNW. Of the tropical cyclones arising in the far end of that ocean to the NE, maybe a quarter of them blunder through this map area; the worst of their force is blunted by a low coastal range, but in addition to normal tropical rainfall, these people get periodic typhoon inundations. Bit of ash-y eruption, bunch of rain, downstream channels clog and open, aaaaand repeat. Ad nauseum. And the ash varies between toxic and fertilizer, so you get vegetation die-offs clogging bayous too, not to mention fish kills occasionally to add to the ambiance.

Can't do text-on-curve with this version of Serif PhotoPlus, so any area labeling I'll drag in from some other program.

This map emphasizes the river nature of those areas between the lakes. It would be just as valid to show pure marsh/ swamp symbols and no main channels, since they change frequently. Indeed, all the intricate threaded water depicted is representational.

If there's time I may do a postcard back, like would be shown if it were a collectors' item in a catalog.

Looks really good! Drawplus will do text on a curve for you! How do you find photoplus for drawing maps? I found the earlier versions tended to crash quite a bit and could not support big file sizes as photoshop could. I've got the latest version of photoplus still in the box - I might give it a go.

Well, I just changed computers, and until I find my photo plus 11 disk & key, I'm stuck with either v5 or their current free version -- which is pretty capable. PhotoPlus suits my workflow pretty well; there's stuff in Gimp & PS tuts I can't do... Yet :-). Some of the cool stuff I'm sure I just need to dig into the docs and play around more. The freebie isn't crashing at all on me. I have locked up v11 with 4gb RAM -- looking forward to trying with 8 !